1 /* Copyright 2015 The Chromium OS Authors. All rights reserved. 2 * Use of this source code is governed by a BSD-style license that can be 3 * found in the LICENSE file. 4 * 5 * Functions for updating the TPM state with the status of boot path. 6 */ 7 8 #include "2sysincludes.h" 9 #include "2common.h" 10 #include "2sha.h" 11 #include "2tpm_bootmode.h" 12 13 /* 14 * Input digests for PCR extend. 15 * These are calculated as: 16 * SHA1("|Developer_Mode||Recovery_Mode||Keyblock_Mode|"). 17 * Developer_Mode can be 0 or 1. 18 * Recovery_Mode can be 0 or 1. 19 * Keyblock flags are defined in 2struct.h and assumed always 0 in recovery mode 20 * or 7 in non-recovery mode. 21 * 22 * We map them to Keyblock_Mode as follows: 23 * ----------------------------------------- 24 * Keyblock Flags | Keyblock Mode 25 * ----------------------------------------- 26 * 0 recovery mode | 0 27 * 7 Normal-signed firmware | 1 28 */ 29 30 const uint8_t kBootStateSHA1Digests[][VB2_SHA1_DIGEST_SIZE] = { 31 /* SHA1(0x00|0x00|0x01) */ 32 {0x25, 0x47, 0xcc, 0x73, 0x6e, 0x95, 0x1f, 0xa4, 0x91, 0x98, 0x53, 0xc4, 33 0x3a, 0xe8, 0x90, 0x86, 0x1a, 0x3b, 0x32, 0x64}, 34 35 /* SHA1(0x01|0x00|0x01) */ 36 {0xc4, 0x2a, 0xc1, 0xc4, 0x6f, 0x1d, 0x4e, 0x21, 0x1c, 0x73, 0x5c, 0xc7, 37 0xdf, 0xad, 0x4f, 0xf8, 0x39, 0x11, 0x10, 0xe9}, 38 39 /* SHA1(0x00|0x01|0x00) */ 40 {0x62, 0x57, 0x18, 0x91, 0x21, 0x5b, 0x4e, 0xfc, 0x1c, 0xea, 0xb7, 0x44, 41 0xce, 0x59, 0xdd, 0x0b, 0x66, 0xea, 0x6f, 0x73}, 42 43 /* SHA1(0x01|0x01|0x00) */ 44 {0x47, 0xec, 0x8d, 0x98, 0x36, 0x64, 0x33, 0xdc, 0x00, 0x2e, 0x77, 0x21, 45 0xc9, 0xe3, 0x7d, 0x50, 0x67, 0x54, 0x79, 0x37}, 46 }; 47 48 const uint8_t *vb2_get_boot_state_digest(struct vb2_context *ctx) 49 { 50 int index = (ctx->flags & VB2_CONTEXT_RECOVERY_MODE ? 2 : 0) + 51 (ctx->flags & VB2_CONTEXT_DEVELOPER_MODE ? 1 : 0); 52 53 return kBootStateSHA1Digests[index]; 54 } 55
